The invention generally relates to lug nuts for wheels and tires. More particularly, the invention relates to a lug nut, which is lockable and unlockable with a use of an individual wrench.
Lockable lug nuts have been used on vehicle wheels to prevent tire theft and to insure the stable attachment of the wheel to the vehicle axle. The conventional lockable lug nut is available in three forms. The first form is composed of a lug nut with a hollow depression at its top with an irregularly surfaced interior insert. The lock or key with a compatible irregular surface is inserted into the nut and force applied to lock or unlock the nut threaded on the lug bolt.
The second conventional lockable lug nut consists of similar construction, though taller than the norm. The interior of the lug nut is threaded, with two opposing interior indentations located at one end of the lug nut. The key is affixed to the cavity apex of a socket, similar to that regularly used in conjunction with a socket wrench. The key has two retractable protrusions located near its base. The socket with the key, when inserted, covers the lug nut. The protrusions engage the indentations and lock the socket with key in place. Force in the form of rotary motion is then applied to fasten or unfasten the nut.
A third form of the prior art is a lug nut and washer apparatus, where the lug nut covers a key and the key engages the washer. The key is cylinder shaped with a flat disc base. A multitude of short prongs are mounted on the underside of the base. The prongs engage corresponding holes on the washer, which then abuts the corresponding holes on the washer, then abuts the key and covering nut. Force is exerted to engage the key and washer, which in turn fastens or unfastens the lug nut and washer apparatus to the bolt.
The above described lug nuts configurations are relatively complicated and therefore difficult to manufacture.
Thus, it is an object of the present invention to provide a car wheel anti-theft device, which is easy to manufacture, yet guarantees an adequate protection against theft.
The present invention provides a car wheel anti-theft device having a lug nut and a sleeve installed onto the bolt of the car wheel and an individual wrench to install and remove the lug nut from the bolt. The sleeve is placed onto the bolt of the car wheel. The lug nut and the sleeve each comprise an engaging flange. When the lug nut is secured on the bolt within the sleeve, the engaging flange of the sleeve engages the engaging flange of the lug nut, thereby preventing the wheel from being moved. In the preferred embodiment, the lug nut comprises a front surface having a key projection of a particular shape.
An individual wrench is provided with the lug nut and sleeve combination of the present invention. The individual wrench includes a cylindrical cavity having a bottom surface. The bottom surface has a key opening extending from the bottom surface towards the depth of the individual wrench. The key opening preferably has a shape complementing the particular shape of the key projection of the lug nut. In order to install or remove the lug nut, a user will align the key opening of the individual wrench with the key projection of the lug nut, insert the key projection into the key opening and then rotate the wrench until the lug nut is installed or removed.
The above and other objects, aspects, features and advantages of the invention will be more readily apparent from the description of the preferred embodiments thereof taken in conjunction with the accompanying drawings and appended claims.